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No, not off the top of my dome, I'll poke around and do some research... O2 sensors are inexpressive replacement parts that should be done at 100k without exception. Simple search produced the following results: Automotive Oxygen Sensor Testing

By Mandy Concepcion

The O2 sensor measures the oxygen content of the exhaust. The O2 sensor's sensing ability comes about by producing a small voltage proportionate to the exhaust oxygen content. In other words, if the oxygen content is low it produces a high voltage (0.90 Volts - Rich mixture) and if the oxygen content is high it produces a low voltage (0.10 Volts - Lean mixture). Although theoretically the O2 sensor should cycle between 0.00 volts and 1.00 volts, in reality it cycles between 0.10 volts and 0.90 volts.

A GM O2 sensor signal stuck at 450 mV is an indication of an open O2 sensor circuit (signal wire) or faulty O2 signal ground. The 450 mV value (GM) is called a bias voltage and it is not the same for all manufacturers. Some manufacturers employ a dedicated O2 sensor ground. Such a ground lead is attached to the engine block or chassis and feeds an ECM O2 ground pin only. The O2 circuit is then grounded through the inside of the ECM electronic board by this ground wire. A loss of this ground would also put the O2 sensor signal at around 450 mV, which also makes it look like an open circuit. The same holds true for Chrysler, but these use a different O2 bias voltage, which is usually 2.00 to 4.00 volts

1) A few key issues are very important in the analysis of O2 sensor signals. 2) An O2 sensor will cycle between 0.10 to 0.90 or almost 1 volt. 3) An O2 sensor has to reach the 0.8x Volts amplitude mark while at full operation. 4) An O2 sensor also has to reach the 0.1x Volts amplitude mark while at full operation. 5) Full operation means the engine is fully warmed up, O2 sensor above the 600 deg. F. operating temperature, and no fuel or mechanical problems present. 6) The O2 sensor must cycle at least once per second, which would show 3 cross counts on the scan tool PID. 7) Silicone is the leading cause of O2 contamination. 8) It is easier for an O2 sensor to go from rich to lean than vise-versa. 9) O2 sensors tend to fail on rich bias. In other words, they tend to shift their cycling to the upper side or rich side of the voltage scale. 10) Contrary to what many people think, an O2 sensor WILL NOT cycle by itself. The O2 sensor cycle is a direct result of the ECM response to the changes in the mixture. 11) Any time the O2 cycles and crosses the 0.450 volts mark, the system is in CLOSE-LOOP. 12) Even though an O2 sensor is cycling and crossing 0.450 volts (ECM in close loop) it DOES NOT mean that it is working properly. 13) O2 sensor operation is extremely important not only to keep HC & CO emissions low but also to the NOx as well. 14) Proper O2 sensor cycling will determine the catalytic converter's efficiency. The catalytic converter needs the O2 sensor cycling at its proper amplitude and frequency for it to function at its maximum efficiency. 15) An O2 sensor with a high voltage reading does not necessarily mean that the mixture is rich or high in fuel content. An EGR valve problem will send the O2 signal high as well.

No, not off the top of my dome, I'll poke around and do some research... O2 sensors are inexpressive replacement parts that should be done at 100k without exception. Simple search produced the following results: http://www.********nosticsandpublish...or-testing.htm

that link doesnt work Z.

__________________

Quote:

Originally Posted by Arsevader
Sorry to hear about your mirror. This is what happens when you don't change your mirror fluid at the recommended intervals.

The O2 sensor measures the oxygen content of the exhaust. The O2 sensor's sensing ability comes about by producing a small voltage proportionate to the exhaust oxygen content. In other words, if the oxygen content is low it produces a high voltage (0.90 Volts - Rich mixture) and if the oxygen content is high it produces a low voltage (0.10 Volts - Lean mixture). Although theoretically the O2 sensor should cycle between 0.00 volts and 1.00 volts, in reality it cycles between 0.10 volts and 0.90 volts.

A GM O2 sensor signal stuck at 450 mV is an indication of an open O2 sensor circuit (signal wire) or faulty O2 signal ground. The 450 mV value (GM) is called a bias voltage and it is not the same for all manufacturers. Some manufacturers employ a dedicated O2 sensor ground. Such a ground lead is attached to the engine block or chassis and feeds an ECM O2 ground pin only. The O2 circuit is then grounded through the inside of the ECM electronic board by this ground wire. A loss of this ground would also put the O2 sensor signal at around 450 mV, which also makes it look like an open circuit. The same holds true for Chrysler, but these use a different O2 bias voltage, which is usually 2.00 to 4.00 volts

1) A few key issues are very important in the analysis of O2 sensor signals. 2) An O2 sensor will cycle between 0.10 to 0.90 or almost 1 volt. 3) An O2 sensor has to reach the 0.8x Volts amplitude mark while at full operation. 4) An O2 sensor also has to reach the 0.1x Volts amplitude mark while at full operation. 5) Full operation means the engine is fully warmed up, O2 sensor above the 600 deg. F. operating temperature, and no fuel or mechanical problems present. 6) The O2 sensor must cycle at least once per second, which would show 3 cross counts on the scan tool PID. 7) Silicone is the leading cause of O2 contamination. 8) It is easier for an O2 sensor to go from rich to lean than vise-versa. 9) O2 sensors tend to fail on rich bias. In other words, they tend to shift their cycling to the upper side or rich side of the voltage scale. 10) Contrary to what many people think, an O2 sensor WILL NOT cycle by itself. The O2 sensor cycle is a direct result of the ECM response to the changes in the mixture. 11) Any time the O2 cycles and crosses the 0.450 volts mark, the system is in CLOSE-LOOP. 12) Even though an O2 sensor is cycling and crossing 0.450 volts (ECM in close loop) it DOES NOT mean that it is working properly. 13) O2 sensor operation is extremely important not only to keep HC & CO emissions low but also to the NOx as well. 14) Proper O2 sensor cycling will determine the catalytic converter's efficiency. The catalytic converter needs the O2 sensor cycling at its proper amplitude and frequency for it to function at its maximum efficiency. 15) An O2 sensor with a high voltage reading does not necessarily mean that the mixture is rich or high in fuel content. An EGR valve problem will send the O2 signal high as well.

Need some help with solving a CEL. Came on about 4 months agowith a 1189 code after I did not put on the gas cap correctly. Reset using my ODB II and all has been fine until recently. Check the gas cap and seemed ok so reset again. This time came up with 1188 and 1189 after about 50 miles. I reset again and the light came on again after abou 10 miles with 1189 only. I did a frame freeze dump and have the following info.

I do have a slight rocker gasket oil leak - could this be the culprit? and could the gas cap also cause this problem? I am not experiencing any performance problems or gas mileage problems - it is just a pain having the light on, and I really DO NOT want to take this into the dealer to solve...I had enough problems with them trying to fix a headlamp flicker problem - a simple grounding issue (they wanted to replace both LCM's at a total cost of >$2k!!!)

I'm fighting these codes too. So far I replaced CCV and hoses, lower boot and no luck. MAF is fine. If u fix these codes post here what was wrong.

Avglushk,
You post alot in other people's threads about your problem to everyone, not everyone's problem for codes isthe same. There is numerous possibilities.

Get a fuel pressure test and a smoke test.
Or your going to waste a lot of money in the long run if you go off of other people's expeiences.
Refer to past problems to find a connection, or a stand out symptom to further diagnose with specific tests. These forums are good for reference and direction.
These guys help out with the checks you can do on your own , like finding a hole in your lower boot, but I can guarantee no one on this forum can read about a problem and 100% nail the problem and fix without proper tests.

You have already thrown parts at your car, (ccv and all hoses) (200$)not to say it's not good preventative maintenance, because it is.

You could keep doing your stratedgy and you will spend more on parts and time, then you would by getting a proper diagnoses.
Just look at those threads were guys list off thousands of dollars in parts they have tried over months and months of banging there heads against the wall, they all end up taking it in for better diagnoses.
Say this guy solves his problem with a fuel pump being the issue, then you go and buy a pump, replace it, find out it doesnt fix the problems. Instead... You should spend 50-80$ on a smoke test and fuel pressure test specifically , and you find out you have a leaking/broken hose. You replace it for 10$ yourself.

well... dude from firestone just called me. He said they did smoke test. No leaks. WTF. He said he's gonna call some technician and see what else could it be. I'll post update after he calls me again.

Avglushk,
You might feel bad that you couldn't find A vaccum leak, but don't be discouraged, you now ruled out 75% of the possible parts being the issue.
You can no move your thoughts over to fuel delivery. (fuel filter,fuel pump,fuel pressure regulator)

Have you ever changed your fuel filter? I would regardless if it is the issue anyways, you can find them online for 10-20$. It's general maintenance and your car is going to love It.

What are all your exact codes again?
And when's the last time your plugs were changed, have u pulled them and taken a look?

Avglushk,
You might feel bad that you couldn't find A vaccum leak, but don't be discouraged, you now ruled out 75% of the possible parts being the issue.
You can no move your thoughts over to fuel delivery. (fuel filter,fuel pump,fuel pressure regulator)

Have you ever changed your fuel filter? I would regardless if it is the issue anyways, you can find them online for 10-20$. It's general maintenance and your car is going to love It.

U r right. I'm not upset. Firestone actually did find something. They found that i dont have a leak

As for fuel filter i replaced that 10-15K ago. I'm thinking O2 sensor. But based on what i read here looks like bad O2 sensor causing car run rich not lean. Am I wrong?

Plugs are fine did them when i had 118K. Now I have almost 153K.

Now I have only one code: p1189

Edit: OK. So the guy called me. Said tested O2 sensors - they are fine. Also did fuel pressure test - fine. He mentioned that air box was missing one clip and MAF sensor connector was a little loose.

__________________

Quote:

Originally Posted by Arsevader
Sorry to hear about your mirror. This is what happens when you don't change your mirror fluid at the recommended intervals.